C program Factorial number

Factorial number - it is iterative multiplication from 1 to a given factorial number. The C program finds decimal value equivalent to given factorial number using iterative manner or for-loop.

Factorial number - example calculation

            find decimal value for given factorial number 
            F =6!

            F = 1 x 2 x 3 x 4 x 5 x 6
            F = 24 x 5 x 6
            F = 120 x 6
            F = 720 
            decimal value 720 is equal to factorial 6! 
   

Factorial - C programming code

The input,factorial number is read from user, while the program is running and calculate result for the factorial number using for-loop.

 
#include <stdio.h>
int main() {

    int x=0; 
    printf("\n Find decimal value for given factorial number");
 
 printf("\nEnter factorial number x :");
 scanf("%d",&x);
 
 int F=1;     
 for (int n=1; n<=x ; n++) {
      F = F * n;  
 } 
          
 printf ("\n Result of Factorial");    
 printf("\n  %d! = %d ",x,F);
 
    return 0;
 }
 
 

 

Factorial - C programming Output

 Find decimal value for given factorial number
 Enter factorial number x
  5

Result of Factorial
5! = 120
 

The C program finds decimal value equivalent to given factorial number using recursive function.

Factorial number using Recursive function - C programming code

The input value,factorial number is read from user and calculate a decimal value as result of the factorial number using recursive function.

 
#include <stdio.h>

int factorial(int f)   {   
 if (f>0)          
     return f*factorial(f-1);
  else  
     return 1;  
  }

int main() 
 {

    int x=0,F=0; 
    printf("\n Find decimal value for given a factorial number");
 
    printf("\nEnter factorial number x :");
    scanf("%d",&x);
 
    F=factorial(x);
    
    printf ("\n Result of Factorial");    
    printf("\n  %d! =: %d ",x,F);
 
    return 0;
 }
 

Output

 Find decimal value for a given factorial number
 Enter factorial number x
  4

Result of Factorial 
4! = 24
 

Download c program source code

• Factorial number using for-loop


• Factorial number using Recursive method